An incompetent tricuspid valve causing tricuspid regurgitation (TR) occurs mainly from tricuspid annular dilation and right ventricular enlargement. TR is often secondary to left heart failure from myocardial or valvular causes, right ventricular volume or pressure overload and dilation of cardiac chambers. TR causes right atrial overload that is transmitted to the superior and inferior vena cava (SVC, IVC) and their tributaries. Eventually, this leads to hepatic congestion, ascites, peripheral edema and other clinical symptoms of congestive heart failure. Historically, tricuspid valve (TV) diseases have received less attention than diseases of the other heart valves. In the last decade, percutaneous transcatheter implantation of aortic and pulmonary valves has become an alternative to open heart surgery, particularly in high risk patients. However, TR did not receive attention of minimally invasive therapy until 2005 when Boudjemline et al developed a stent valve device and tested it in sheep to replace for their normal TV. Bai et al used a similar double-edge stent device for implantation into normal TVs in sheep. Both groups were successful in the majority of sheep tested, but expressed concern about device fixation, embolization, and the risk of myocardial trauma.
Placement of a self-expandable valve stent into the IVC between the hepatic vein origins and cavoatrial junction was first explored in normal swine by Como et al in 2003 as a potential treatment for failing total cavo-pulmonary connection. In a 2008 overview article on percutaneous replacement of heart valves, the same group mentioned placement of stent valves into the SVC and IVC for treatment of TR. Davidson & Cohn reviewing percutaneous valve repair in 2009 then referred to a case report of the use of stent-based valves in the SVC and IVC as functional replacement of TV. No procedure details and results were given and the case was referred as a case study presented at a Cleveland Clinic conference in 2006 by R. Greenberg.
The present invention is addressed to these and other concerns and improvements.